Wildfires

• Type of Wildfire

  • Crown - Spread across canopy
  • Surface - Spread across ground vegetation
  • Ground - Spread beneath the surface
• Conditions

  • Supply of fuel (vegetation)
  • Ignition - Power lines, lightning, arson
  • Dry climate
• Black Saturday geographical processes

  • 46 degrees
  • windspeed over 100km/hr
  • flamespeed over 12km/hr
  • 2 month drought
• Black Saturday Impacts

  • 173 people died, 414 injured, 2000 homes destroyed, 7562 displaced
  • 450,000 HA destroyed
  • Over 1,000,000 dead animals
  • Water supplies contaminated in Melbourne
  • Power cuts for 60,000 people
  • 11,000 livestock killed
  • Cost $4.4 billion
• Responses

  • 4,000 Australian firefighters, 1,000 from New Zealand
  • international aid from Commonwealth
  • Elizabeth II sent donations to Red Cross
  • $8.8 million raised for victims
• Wildfire Positive feedback loop

  1. wildfire ignited
  2. rapid evapotranspiration
  3. more moisture in atmosphere
  4. ash rises
  5. pyro cumulonimbus clouds form
  6. higher electrical charge
  7. increased risk of lightning (ignition)
• El Nino

  • Cyclical climate condition
  • every 6-8 years
  • Trade winds usually transport warm pacific winds to Western Australia
  • This leads to low pressure and high evaporation
• Preparedness

  • Social media warnings - Facebook
  • Satellites and infrared sensors
• Prevention

  • Removal of Dead vegetation
  • Public awareness - Smokey Bear warnings in US - 70% recognise it
  • Encouraging visitors to act sensibly
• Mitigation and Adaptation

  • Removal of vegetation
  • Back Burning
  • Natural barriers - rivers
  • buildings integrated into the environment
• Australia's geography

  • Dry climate
  • prevailing trade winds
  • volatile vegetation - Eucalyptus trees